Super-sharp seniors’ brains.

Researchers at Massachusetts General Hospital study older people whose mental sharpness is comparable to that of 25-year-olds, termed “superagers.” Using fMRI technology, the study finds marked differences between superagers and “normal” seniors in the major hub areas of the limbic system, principally comprising the amygdala, hippocampus, thalamus, hypothalamus, basal ganglia, and cingulate gyrus (see Brain Facts-Memory and Learning). The thicker these regions of the cortex are, the better individuals score on memory and attention performance tests.